Hi i am working on a project were i have a power source, a resistor, then an LED.by using a resistor and limiting the power to the LED will that make the life of my battery longer? any help would be greatly appreciated, thnx :-)

 Not if you type your question in caps.  Yes, but most LED use little power anyway.
appolo8 years ago
Most LED's generally operate at around 20Ma. Lemonie's suggested link will help you. However_by increasing the value of the series resistor you are increasing the resistance to the flow of current, the current is in series so will reduce proportionaly to the increase in resistance. You can continue to increase the value of your resistance if you wish, the LED brightness falls of course but at some point you will achieve a state of adequate brightness level with an increase value of series resistance, and as a result less curent draw from you battery means greater operating life span. Also as a foot note the power dissipated in the resistor falls as less current flows through it when its resistance is increased.
All things considered, no, the power not dissipated in the LED is dissipated by the resistor, and you have to have a resistor to limit diode current. For high efficiency you need to run the LED from some electronics.
lemonie8 years ago
It should help.
Classic LED link: http://led.linear1.org/1led.wiz